Hello,
Some back story... I purchased a 2000 4runner a few weeks ago that was in incredible shape but had some issues idling / accelerating.
After researching on this list, the idle and accelerating issues was due to a very dirty MAF. Cleaned it, and all the problems went away, except for a p0135 code.
The exhaust has a factory 2 Catalytic system, that matches the California Spec.
I ordered a A/F sensor from Toyota, because that's what the connector fits, and what the 2 Cat system wants...
However, the original sensor in the car had 2 sides shaved down...
The new a/f sensor plugged right in but gave me the same p0135 code.
I then realized that the ECU was a Federal ECU, and the wiring for the sensors heater was different.
I then got myself a proper Toyota O2 sensor, had to shave down 2 sides of it, and rewire the ground for the heater circuit as its the only pin different on the ECU.
Code is gone, vehicle is running good, but consuming a lot of fuel.
It seems the ECU at some point was switched to a Federal ECU, the o2 sensor was installed, but its had the p0135 code for almost 7 years now and has not passed emissions until I corrected the wiring at the ecu. (No more CEL)
My real question is, would I gain anything by installing a California ECU and putting in a proper A/F Sensor? Would this give me a better running engine with better fuel mileage?
Sorry for the long post, its been a weird one!
P.S. The VIN is no longer original as it was a full rebuild 10 years ago after a large insurance claim, so the VIN is now a replacement VIN that does not actually give me or Toyota any information on the vehicle.
Thanks,
Paul
Some back story... I purchased a 2000 4runner a few weeks ago that was in incredible shape but had some issues idling / accelerating.
After researching on this list, the idle and accelerating issues was due to a very dirty MAF. Cleaned it, and all the problems went away, except for a p0135 code.
The exhaust has a factory 2 Catalytic system, that matches the California Spec.
I ordered a A/F sensor from Toyota, because that's what the connector fits, and what the 2 Cat system wants...
However, the original sensor in the car had 2 sides shaved down...
The new a/f sensor plugged right in but gave me the same p0135 code.
I then realized that the ECU was a Federal ECU, and the wiring for the sensors heater was different.
I then got myself a proper Toyota O2 sensor, had to shave down 2 sides of it, and rewire the ground for the heater circuit as its the only pin different on the ECU.
Code is gone, vehicle is running good, but consuming a lot of fuel.
It seems the ECU at some point was switched to a Federal ECU, the o2 sensor was installed, but its had the p0135 code for almost 7 years now and has not passed emissions until I corrected the wiring at the ecu. (No more CEL)
My real question is, would I gain anything by installing a California ECU and putting in a proper A/F Sensor? Would this give me a better running engine with better fuel mileage?
Sorry for the long post, its been a weird one!
P.S. The VIN is no longer original as it was a full rebuild 10 years ago after a large insurance claim, so the VIN is now a replacement VIN that does not actually give me or Toyota any information on the vehicle.
Thanks,
Paul
